Feature: 1. 2.8-inch large screen simultaneously display the current CO2 concentration, temperature, humidity and battery indicator. 2. 1s automatic refresh detection data, real-time monitoring, stable and reliable. 3. 4pcs color light bar(green, yellow, orange, and red) indicate for the corresponding CO2 concentration. 4. One button control, short press to switch the temperature unit between ℃ and ℉, long press to ON/OFF the detector. 5. Built in with 1200mAh rechargeable lithium battery, no need to change battery, economical and environment-friendly. 6. Compact portable size with simple modern appearance, suitable for home, office, dormitory, warehouse, etc. Specification: Features: 2.8-inch large screen simultaneously display the current CO2 concentration, temperature, humidity and battery indicator. 1s automatic refresh detection data, real-time monitoring, stable and reliable. 4pcs color light bar(green, yellow, orange, and red) indicate for the corresponding CO2 concentration. One button control, short press to switch the temperature unit between ℃ and ℉, long press to ON/OFF the detector. Built in with 1200mAh rechargeable lithium battery, no need to change battery, economical and environment-friendly. Compact portable size with simple modern appearance, suitable for home, office, dormitory, warehouse, etc. Specifications: Color: Black / White (Optional) Material: ABS CO2 Detection Range: 400~5000PPM CO2 Detection Sensitivity: 1PPM Temperature Measurement Range: 0~50℃ Temperature Measurement Accuracy: ±1℃ Humidity Measurement Range: 0%-99%RH Humidity Measurement Accuracy: ±5%RH Anti-interference: 47.22% Respond Time: ≤60s Working Voltage: 3.7V Charging Mode: USB 500mA Type-C interface Battery: 1200mAh built-in lithium battery Item Size: 90 * 70 * 40mm / 3.54 * 2.76 * 1.57in Item Weight: 146g / 5.18oz Package Weight: 220g / 7.78oz Package Size: 11.5 * 11.5 * 4.5cm / 4.53 * 4.53 * 1.77in Packing List: 1 * Detector 1 * Charging Cable Package List: 1 * Detector 1 * Charging Cable